<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="../js/util/jquery-3.4.1.min.js"></script>
    <script src="../js/groupManage.js"></script>
</head>
<body>
    <select id="nni">

    </select>
    <button onclick="bubu()">nihao</button>
<div id="ll"></div>
</body>
</html>